This invention relates in general to new and useful improvements in mobile outdoor equipment vehicles, such as concrete trucks and other construction vehicles. In particular, this invention relates to preventing fluids carried inside such vehicles from freezing in below freezing ambient conditions. Although this invention is primarily envisioned to prevent the water inside concrete trucks from freezing, other outdoor equipment or fluid bearing structures might employ this invention, such as industrial supply vehicles or non-flammable industrial fluids.
Conventionally, concrete trucks must carry water in their water tanks to thin concrete mix when arriving at a job site. This water is transported through various fittings and hoses within the truck and is also used to wash down the concrete chute when the job is completed. The water in such trucks must be pure and cannot contain additives such as antifreeze, which lower the quality of the concrete product. During winter months when temperatures fall below the freezing point of water, the water inside the trucks can freeze inside the valves, fittings, hoses, and tanks.
To prevent freezing water from damaging concrete trucks, operators must empty the tank and wash down the chute each night. The hoses, valves and fittings must also be drained of water. These tasks waste water and create unsafe conditions for the operators due to the drained water freezing in puddles around the trucks.
Furthermore, man hours are wasted and precious fuel is consumed because water tanks need to be refilled, forcing the truck to leave the site and return the next day. Compensation for the additional man hours spent emptying and filling tanks must be charged to the construction job budget, which increases the overall cost of the job to the client. Wasted water from draining and refilling water tanks also causes a strain on this limited natural resource.
Thermal and insulating jackets have been used to keep the concrete in a workable condition while in the drum through adverse weather conditions. U.S. Pat. Nos. 7,793,691 and 6,264,361 attempt to address the problem of keeping the concrete in a plastic state while in the drum by using an insulator for the drum. However, these issues are different than the problem in keeping the water supply in a liquid state if subjected to below freezing conditions. A solution to this problem could not be found in the prior art as concrete truck operators generally avoid working in these conditions or sacrifice the man hours as described above to complete jobs.
Due to the lack of viable systems to counteract the problem of freezing water in concrete trucks, there remains a need for a heating system that can maintain the temperature of the water inside such concrete trucks above freezing. Such a system will eliminate the man hours wasted in emptying the water from the trucks each night during winter months, which will also eliminate the associated waste of water. A heating system for concrete trucks will also help preserve the safety of the operators by eliminating frozen water puddles around the job site.